The present invention relates generally to a dynamic counterweight mechanism for one sided sprayers and, more particularly, relates to a dynamic counterweight mechanism for such one-sided sprayers used with air assistance on creeping, vine plants, or creepers, such as potatoes, pumpkins, melons, and vegetable in general, where it is not possible to enter the plant rows due to the crop""s characteristics, for example, crops on flooded ground.
As is known in the current state of the art, tractors that must pass through the tracks for vehicles in general pull the one-sided boom sprayers. In this manner, these spray booms must have a length equivalent to two consecutive tracks, which generates a balance problem on the tractor and spray-boom assembly.
Because this one-sided sprayer lacks a spray boom on the opposite side of the sprayer, in order to obtain a counterbalancing of the assembly, a non-adjustable block-shaped counterweight is typically provided on the opposite side of the sprayer. This counterweight is positioned oppositely to the spray boom to eliminate the unbalance and minimize the moment force between the boom and the vehicle that pulls the boom.
Therefore, one object of the present invention is to provide a dynamic counterweight mechanism for one-sided sprayers that ensures an adequate balance of the spray boom, which prevents the sprayer from turning over.
Another purpose of the present invention is to provide a dynamic counterweight mechanism for one-sided sprayers that allows a permanent and constant compensation of the angular variation between the spray boom and the ground, thereby always ensuring a parallelism between them.
A further object of the present invention is to provide a dynamic counterweight mechanism for one-sided sprayers that allows the balance standard or level made between the counterweight and the spray boom to adjust itself, maintaining it always at a preset level relative to the ground.
Yet another purpose of the present invention is to provide a dynamic counterweight mechanism for one-sided sprayers that allows a significant reduction of the counterweight mass.
Thus, a main purpose of the present invention is to provide a dynamic counterweight mechanism for one-sided sprayers that can meet the need for spraying creepers with the assistance of long booms assembled in balance on just one side of the spraying implement.
These are other purposes and advantages of the present invention are attained with a dynamic counterweight for one-sided sprayers that is based on a conventional sprayer, consisting of a chemical tank, a pump for the circulation of the chemical mixture stored in the tank, and a hydraulic pump that actuates a structural system formed by a frame and booms. All of these components are disposed on a chassis. This system must be balanced by the counterweight. According to the present invention, the counterweight mechanism is consisted of rigid columns vertically fastened to the chassis, on which a fixed vertical frame is mounted, on which a frame slides up-and-down, laterally sustaining a counterweight module. The counterweight module is defined by a pair of vertical guides set in a parallel manner and spaced from one another, with a counterweight assembled in a sliding way in the space between them. On the opposite side of the sliding frame, a swinging module is assembled pivotally, defined by a vertical profile, and having a supporting base comprising horizontal profiles, while the vertical profile is fitted medially in a bearing in the vertical part of the sliding frame. The swinging module rotates around this bearing and in relation to the sliding frame and has its upper end interconnected to the counterweight module. The counterweight block of the counterweight module moves up and down due to the displacement of the swinging module. The suspended counterweight block is sustained by a steel cable that is faxed on its upper wall and extended by a set of sheaves between the swinging module and the sliding frame, thereby allowing the steel cable to run about the set of pivoted sheaves on the sliding frame and on the swinging module to multiple the nominal weight of the counterweight block acting on the longer spray boom.
The counterweight module comprises at least a traction spring, having one end connected to the swinging module, while on its opposite end, it is connected to a traction-adjusting threaded shaft, which, in turn, is held on the sliding frame. The swinging module has an angular displacement that is deadened by progressive action cushions fitted on the sliding frame. The inventive dynamic counterweight mechanism further includes a quadrangular structure, which is held by the horizontal profiles as a supporting base of the swinging module, in addition to being pivotally retained to the vertical profile through a vertical shaft disposed thereon. The quadrangular structure is subjected to rotating or moving angularly around this shaft, according to a transversal plane in relation to the swinging module. The angular displacement of the quadrangular structure is also deadened on its ends by rubber cushions.